The present invention generally relates to a signal separator for separating model songs in a Karaoke apparatus using a media where accompaniments only are recorded as first signals on a channel 1, and accompaniments and model songs as second signals are recorded on a channel 2.
The Karaoke apparatus is an appliance for song accompaniments developed in Japan. It is used for singing with the use of a microphone while reproducing accompanied music recorded previously on recording media. In recent years, the Karaoke apparatus has various functions of detecting the existence of the model songs recorded on the recording media so as to indicate a song starting portion, reproducing the model songs automatically when a user cannot sing continuously, because he forgets his words, displaying on picture scenes intervals of the model songs and the user's songs, and the others.
A voice multiplex Karaoke laser disk put on the market at present has voice signals of four channels recorded in total, namely, two channels of digital voices and two channels of analog voices. Two channels of digital voices have the accompaniments recorded in stereo. The L (left) channel of analog has the accompaniments only recorded, and the R (right) channel thereof has the accompaniments and the model songs recorded. The accompaniments recorded on the analog L channel, and the Right channel are the same signals.
A prior material of the conventional Karaoke apparatus provided with a function of drawing out model song signals only from the analog voices of the voice multiplex Karaoke laser disk is disclosed in the Title of the Invention, for example, "Karaoke apparatus" in Japanese Patent Laid-Open Publication No. 5-165398.
The conventional signal separator will be described hereinafter with reference to the drawings.
FIG. 14 is a block diagram showing the construction of the conventional signal separator.
In FIG. 14, reference numeral 1101 is an analog L (left) signal input terminal, reference numeral 1102 is an analog R (right) signal input terminal, reference numeral 1103 is a subtracter for subtracting L signals from R signals, reference numeral 1104 is an output input. Since the accompaniments only are recorded on the L (left) channel of the analog and the accompaniments and the model songs are recorded on the R (right) channel by the above described construction, the model song signals only are outputted to the output terminal 1104.
The above described conventional construction has a problem that only the model songs cannot be drawn out when the recording level of the accompaniments of the L signals is different from the recording level of the accompaniments of the R signals. The voice multiplex Karaoke laser disk put on the market often has the accompaniment level of the R signals lower than the accompaniment level of the L signal in order to add the model songs. The accompaniment level of the L signal and the R signal is different not only on desk, but also on each piece even in the same disk. Therefore, the conventional construction cannot damp the accompaniments sufficiently in a piece so that the function of using the model song signals may cause error operations.